术中输注氨基酸对胃肠道手术患者脂代谢和体温的影响

 目的 研究术中静脉输注氨基酸对在硬膜外阻滞复合全麻下行胃肠道手术患者脂肪代谢和体温的影响。方法 选择择期行胃肠道手术患者32例，ASAⅠ~Ⅱ级，随机分成两组（n=16）：分别在麻醉诱导同时输注18-氨基酸混合液4 KJ·kg^-1·h^-1（即2 mL·kg^-1·h^-1，AA组）和乳酸钠林格氏液2 mL·kg^-1·h^-1（LR组）直至手术结束。监测麻醉前30 min，诱导后手术开始前，手术开始后30 min、2 h，手术结束后30 min、2 h的鼻咽温度，血清胆固醇、三酰甘油、游离脂肪酸（free fatty acid，FFA）浓度和血酮体的变化。结果 两组术中鼻咽温度均呈下降趋势，但AA组手术开始后2 h鼻咽温度显著高于LR组（P<0.05），手术结束后两组温度有所回升，AA组手术结束后2 h鼻咽温度［（36.89±0.13）℃］较麻醉前30 min［（36.98±0.13）℃］差异无统计学意义（P>0.05），且显著高于LR组［（36.10±0.15）℃］（P<0.05），LR组仍显著低于麻醉前30 min［（37.04±0.15）℃］（P<0.05）；两组术中血清胆固醇浓度均呈下降趋势，手术开始后30 min至手术结束后2 h浓度较麻醉前30 min显著降低（P<0.05），而两组间差异无统计学意义（P>0.05）；诱导后手术开始前两组的血清三酰甘油浓度均较术前显著升高（P<0.05），LR组手术结束后2 h浓度［（0.71±0.27）mmol/L］较麻醉前30 min［（0.99±0.38）mmol/L］显著降低（P<0.05），而在AA组差异无统计学意义（P>0.05）；两组手术开始后30 min、2 h血清 FFA浓度均显著低于麻醉前30 min（P<0.05），且AA组［（0.52±0.15，0.42±0.09）mmol/L］显著低于LR组［（0.81±0.24，0.82±0.22）mmol/L，P<0.05］，而手术结束后2 h浓度AA组［（1.04±0.28）mmol/L］显著高于LR组［（0.82±0.16）mmol/L，P<0.05］；两组围术期各时间点血酮体均为阴性。结论 术中输注氨基酸可减少硬膜外阻滞复合全麻下行胃肠道手术患者体温的降低，并抑制脂肪动员。

Effect of intraoperative amino acids infusion on the metabolism of fat and body temperature in the patients undergoing gastrointestinal surgery

Objective To study the effect of intraoperative amino acids infusion on the fat metabolism and body temperature in the patients undergoing gastrointestinal surgery under general anesthesia combined with epidural block. Methods Thirty-two patients scheduled for gastrointestinal surgery were randomly assigned to receive either compound amino acid　injection (18AA-Ⅱ) (group AA) or lactated Ringer’s solution (group LR) at a rate of 4 KJ·kg^-1·h^-1 (2 mL·kg^-1·h^-1) from the induction of anesthesia to the end of surgery. Nasopharyngeal core temperatures were measured, and serum cholesterol, triglyceride, free fatty acid (FFA) and ketone bodies were analyzed before, during and after the surgery. Results Nasopharyngeal temperature declined during the surgery in both groups, however, the temperatures at 2 hours after the beginning of surgery in AA group were significantly higher than those in LR group (P<0.05). Nasopharyngeal temperatures rebounded after the surgery. The temperature at 2 hours after the surgery in AA group (36.89±0.13)℃] was significantly higher than that in LR group (36.10±0.15)℃] (P<0.05), which significantly decreased compared with 30 minutes before anesthesia (37.04±0.15)℃] (P<0.05). Compared with 30 minutes before anesthesia, serum cholesterol concentrations significantly decreased from 30 minutes to 2 hours after the surgery in both groups (P<0.05), while there was no statistical difference between the two groups (P>0.05). Compared with 30 minutes before anesthesia, serum triglyceride concentrations after the induction of anesthesia were significantly higher in both groups (P<0.05) and significantly decreased at 2 hours after the surgery in LR group (P<0.05), however, it did not change significantly in AA group (P>0.05). Serum FFA concentrations at 30 minutes and 2 hours after the beginning of surgery in AA group (0.52±0.15, 0.42±0.09) mmol/L] were significantly lower than those in LR group (0.81±0.24, 0.82±0.22) mmol/L, P<0.05]. Meanwhile, serum FFA concentration of AA group at 2 hours after the surgery (1.04±0.28)mmol/L] was significantly higher than that in LR group (0.82±0.16)mmol/L, P<0.05]. All the ketone body tests were negative. Conclusions Intraoperative infusion of amino acids can effectively prevent hypothermia during and within 2 hours after the surgery, and inhibit lipid mobilization.